In preparation for checking whether the architecture has data cache aliasing within alloc_dax(), modify the error handling of dm alloc_dev() to treat alloc_dax() -EOPNOTSUPP failure as non-fatal.
Fixes: d92576f1167c ("dax: does not work correctly with virtual aliasing caches") Suggested-by: Dan Williams <dan.j.willi...@intel.com> Signed-off-by: Mathieu Desnoyers <mathieu.desnoy...@efficios.com> Reviewed-by: Dan Williams <dan.j.willi...@intel.com> Cc: Alasdair Kergon <a...@redhat.com> Cc: Mike Snitzer <snit...@kernel.org> Cc: Mikulas Patocka <mpato...@redhat.com> Cc: Andrew Morton <a...@linux-foundation.org> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Dan Williams <dan.j.willi...@intel.com> Cc: Vishal Verma <vishal.l.ve...@intel.com> Cc: Dave Jiang <dave.ji...@intel.com> Cc: Matthew Wilcox <wi...@infradead.org> Cc: Arnd Bergmann <a...@arndb.de> Cc: Russell King <li...@armlinux.org.uk> Cc: linux-a...@vger.kernel.org Cc: linux-...@vger.kernel.org Cc: linux-fsde...@vger.kernel.org Cc: linux...@kvack.org Cc: linux-...@vger.kernel.org Cc: dm-devel@lists.linux.dev Cc: nvd...@lists.linux.dev --- drivers/md/dm.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 23c32cd1f1d8..acdc00bc05be 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -2054,6 +2054,7 @@ static void cleanup_mapped_device(struct mapped_device *md) static struct mapped_device *alloc_dev(int minor) { int r, numa_node_id = dm_get_numa_node(); + struct dax_device *dax_dev; struct mapped_device *md; void *old_md; @@ -2122,15 +2123,15 @@ static struct mapped_device *alloc_dev(int minor) md->disk->private_data = md; sprintf(md->disk->disk_name, "dm-%d", minor); - if (IS_ENABLED(CONFIG_FS_DAX)) { - md->dax_dev = alloc_dax(md, &dm_dax_ops); - if (IS_ERR(md->dax_dev)) { - md->dax_dev = NULL; + dax_dev = alloc_dax(md, &dm_dax_ops); + if (IS_ERR(dax_dev)) { + if (PTR_ERR(dax_dev) != -EOPNOTSUPP) goto bad; - } - set_dax_nocache(md->dax_dev); - set_dax_nomc(md->dax_dev); - if (dax_add_host(md->dax_dev, md->disk)) + } else { + set_dax_nocache(dax_dev); + set_dax_nomc(dax_dev); + md->dax_dev = dax_dev; + if (dax_add_host(dax_dev, md->disk)) goto bad; } -- 2.39.2